I'm getting the error "sync failed. Awaiting next sync" on the ADE page. I'm also getting a similar error in another MDM we have. Is there an issue with Apple's ADE sync right now?
We had the same thing. Once or twice a year we are obliged to renew the certificate.
I also had the same thing. I followed the instructions (or so I thought I did).
The step I missed for some reason was "Click [Save]" after uploading the file. That fixed the problem.
Hope this helps someone.